{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "c078ca3b0c5bf82c2b31906c446d6e2ad8ea0783"
            },
            {
              "fixed": "8738b1b6d0e639ca1fc0f61516afd3557ac4ecc6"
            },
            {
              "fixed": "19748967d59c31d24d21d40b728570788310b237"
            },
            {
              "fixed": "46fc15a044e9938e7ea77786fb37edd2cd74f031"
            },
            {
              "fixed": "cd513e43b4b2bd1de39e2367bc4261c699a8652f"
            },
            {
              "fixed": "67b27434c43b68a97becda98c9f0c8cf6cba2134"
            },
            {
              "fixed": "78069a6d8bc86c9e036eb82c2af4a19cc1871a53"
            },
            {
              "fixed": "f08fb3d42fd3aad0b7a263da3ac3ebaf0845e265"
            },
            {
              "fixed": "772cecf198da732faebb5dcfc46d66a505be8495"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.11.0"
            },
            {
              "fixed": "5.10.259"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.210"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.176"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.143"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.94"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.36"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53218.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_exthdr: fix register tracking for F_PRESENT flag\n\nnft_exthdr_init() passes user-controlled priv-\u003elen to\nnft_parse_register_store(), which marks that many bytes in the\nregister bitmap as initialized.  However, when NFT_EXTHDR_F_PRESENT\nis set, the eval paths write only 1 byte (nft_reg_store8) or\n4 bytes (*dest = 0 on TCP/DCCP error path).  When len \u003e 4,\nregisters beyond the first are never written, retaining\nuninitialized stack data from nft_regs.\n\nBail out if userspace requests too much data when F_PRESENT is set.",
  "id": "CVE-2026-53218",
  "modified": "2026-07-08T05:38:41.323810Z",
  "published": "2026-06-25T08:39:21.069Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/19748967d59c31d24d21d40b728570788310b237"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/46fc15a044e9938e7ea77786fb37edd2cd74f031"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/67b27434c43b68a97becda98c9f0c8cf6cba2134"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/772cecf198da732faebb5dcfc46d66a505be8495"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/78069a6d8bc86c9e036eb82c2af4a19cc1871a53"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8738b1b6d0e639ca1fc0f61516afd3557ac4ecc6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cd513e43b4b2bd1de39e2367bc4261c699a8652f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f08fb3d42fd3aad0b7a263da3ac3ebaf0845e265"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53218.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53218"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "netfilter: nft_exthdr: fix register tracking for F_PRESENT flag"
}